#! /usr/bin/env python
#coding=utf-8
def g():
    print 'step 1' 
    x = yield 'hello'
    print 'step 2', 'x=', x 
    y = 5 + (yield x) 
    print 'step 3', 'y=', y 
def h():
    print 'abc'

if __name__ == '__main__':
    f = g()
    f.next()
    f.send(5)
    h()